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Subject: Re: IDE disk and HPA
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Oliver Tennert <O.Tennert@science-computing.de>
Cc: linux-kernel@vger.kernel.org
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Date: Fri, 22 Jul 2005 15:47:18 +0100
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> Do I interpret it right that the following is done in the above function:

Aside from the version in most kernels being buggy yes

> My question is now: why is an HPA disabled i.e. disprotected when detected? 
> Why not let the HPA alone, because a certain set of disk sectors shall not be 
> accessible by the OS?

Because the HPA is most commonly used to hide all but a fraction of a
disk to work with older BIOSes.